New rtlsdr Plugin

[delcrest]

Hi everyone, after much guess work trial and error I have at last got my ais dongle DVB=T+DAB working on my win8.1 laptop
I am getting good signals from ships 40+NM away and some even much further which makes me wonder about the accuracy of the software, granted I am not on the boat but about 19KM inland and high above sea level with a good view of the ocean on the horizon
The problem I have is I cant get opencpn to see the aismon information, unless I am connected to my router
In Aismon the IP address flashes red, and nothing shows on cpn , plug the router cable into the laptop and it works great!! IP address stops flashing red and tragets show on opnecpn
Anyone know a way around this please, thanks in advance

[delcrest]

picture added of ais targets

[rgleason]

Delcrest or anyone else. What are the step by stepprocedures you used to get it working in Opencpn, please include driver install.

[rgleason]

Maelruan
Would it be easier and better to make and install a slim jim antenna in a pcv or fg tube? Would mounting it onto my 9' high backstay radar antenna ve gifh enough?
Should the antenna be vertical or can it be mounted about 3" off the backstay aligned with the backdtay,

[delcrest]

Originally Posted by rgleason

Delcrest or anyone else. What are the step by stepprocedures you used to get it working in Opencpn, please include driver install.

HI please don't shoot me down as I am not computer literate and now to old to understand all this new pc stuff
I found at that the dongle would only run correctly with the program HDSDR, and the drivers ExTIO_RTL.DLL and ExTIO_RTL2832.dll and zadig 2.12
when I open HDSDR I am asked to choose which driver to use, I select ExTIO_RTL2832.dll and then start the hdsdr select fm, frequency manager and try tuning the the dongle at the ais frequency
I am using a ais antenna which I purchased from a local radio shop, which if the software is correct I am getting signals from ships nearby and very very far away like 800kms, I think this could be skip, signal bounce as sometime get with cb radio
I used virtual audio to link ais mon and hdsdr
But I still have a problem with the aismon IP addess flashing red and CPN not seeing the targets unless I have my router connected to the laptop I am using a HP laptop running win8.1
If you PM me with your email address I can I will email you with screen dumps and the drivers I used, sorry I don't know how to post a picure that is large enough on CF

[Maelruan]

Hi RGleason,
The reply I posted yesterday to your query seems lost.
The SlimJim is very easy to fit into a 1" waste water PVC tube. Bung it each end & seal with amalgamating tape. The higher it's mounted the better the range, as signals in this part of the EM spectrum are line of sight, plus a little refraction, and some times reflection. I've read that the radiation pattern is in the form of a doonut on a plane 90 degs to the antenna, so if it is tilted then part of the radiation is tilted skywards & part to ground.
There is a limit to the value of these setups, as a new VHF with AIS can be purchased for as low as 200 Euro, e.g. see these specs:
integrated with dual channel AIS (Automatic Identification System) receiver for your safery aid on the sea. It monitors AIS channels (161.975/162.025) and receives AIS data from vessels fitted with AIS class A or B transponder around your vessel. It is simplified unit with no AIS display. Received AIS data is automatically
transferred to a connected plotter via NMEA interface.
Also it has class-D DSC capabilities meets the EN 301-025 with inside separated CH70 watch receiver. Position Send/Request functions are available. Construction is waterproof equivalents to the JIS-7.

Features include:
• Built-in dual channel AIS receiver
• Transfer the received AIS data to a plotter
o NMEA VDM sentence output at 38400 baud.
o Need to connect to an AIS capable plotter.

[rgleason]

Delcrest,

HDSR
I too found that HDSDR and download file suggested on the website, unzip and then load HDSDR and choose ExTIO_RTL2832.dll , works with the dongle. Your description is helpful.

Virtual Audio used to link Aismon and HDSDR.

But I still have a problem with the aismon IP addess flashing red and CPN not seeing the targets unless I have my router connected to the laptop

So what is the Aismon IP address being used? Perhaps you should advise where that information is found for others. Also what IP have you entered into Opencpn Options > Connections? By being more specific you will help others.

-I will also try to do the same. Thanks for sharing.

It sounds to me like your networking card needs to be operational for the IP address to be recognized, even though Opencpn has a network server. Someone is going to know what is happening, but try to be more specific about the details.

I have not been able to get the dongle recognized in Opencpn, this is some progress!

[delcrest]

HI the ip address in cpn connections is 127.0.0.1:10110 The same as aismon
yes I think
It sounds to me like your networking card needs to be operational for the IP address to be recognized "" you are correct . but this could be a win 8.1 issue, Been thinking about downloading a virtual com driver but afraid it could cause other issues that I cant resolve myself

[rgleason]

Thought I'd follow this step by step and get that right. Then try Opencpn
Software Defined Radio for Mariners: Beginner - Software
"By the end of this guid you will be able to use your RTL stick with SDRSharp" ---

But I am going to use most current SDRsharp and the more current

Zadig 2.1.2 Driver
http://sourceforge.net/projects/libwdi/files/zadig/ <-- Source
but newer ones are here http://zadig.akeo.ie/
Click on Zadig for Windows Vista or later (5.0 MB) unless you have XP You will probably download Zadig 2.1.2
When installing "Run as Admin" - Right click and pick it.

Getting it to work in Windows 10
http://www.rtl-sdr.com/tag/zadig/

Install SDRsharp
http://sdrsharp.com/#sdrsharp

-----
Alternative Install for HDSR
http://www.hamradioscience.com/alter...cks-and-hdsdr/

HDSR http://www.hdsdr.de/
This needs a driver, here is also an example ExtIO DLL with sources as public-domain, developed with Microsoft Visual C++ 2008 Express Edition.

[rgleason]

This is best for Zadig install Zadig - USB driver installation made easy

[rgleason]

RTLSDR-Scanner uses python
I really like this one, it lets me know whether the driver is the right one and is easy to use. Does scans and paints it over a screen so you can see the addittive result.
Very smart Idea.
RTLSDR Scanner | Ear to Ear Oak

[rgleason]

Here is the screen around AIS after 17 scans.
With a bad antenna tiny one, indoors.

[conachair]

Originally Posted by rgleason

RTLSDR-Scanner uses python
I really like this one, it lets me know whether the driver is the right one and is easy to use. Does scans and paints it over a screen so you can see the addittive result.
Very smart Idea.
RTLSDR Scanner | Ear to Ear Oak

Ta for that link, very useful prog, up and running on linux now. Just a pity it would run a funcube proplus dongle.

[piluso]

Originally Posted by rgleason

Here is the screen around AIS after 17 scans.
With a bad antenna tiny one, indoors.

The AIS frequencies are 161.975 Mhz and 162.025 Mhz, both channels are outside the graph; the frequencies shown are not AIS related. Would be nice if you can narrow the spectrum to about 200Khz: 161.9 Mhz - 162.1Mhz

Regards, David

[rooiedirk]

I've made a few changes to rtl_ais. There is a hacked version of the library on the net that gives a few extras.
. For the compiling there is now cmake. (Go to the build directory. do #cmake .. and then make.)
. added also rtl_test. this will allow to find the ppm. (rtl_test -p)
. added an option (-w) to enter a bandwidth. default is as narrow as possible.
. for linux the kernelmodule is now auto deattached. So no more blacklisting.
. the library is now compiled into the program. So only one executable file.

TODO
There is also a hack to increase the HF gain. would be nice.
Split the aisdecoder in a few seperated threads. I think this will increase the number of received sentences.

This version is on https://github.com/RooieDirk/rtl_ais